The stratigraphic abundances of foraminifera such as this are being used to determine the age of the London Clay.
In the most general terms these are related to the study of geological controls of geotechnical parameters. These can range in scale from the nanometer to kilometer. They consider the materials that make up soils and rocks, the fabric and structure of those materials, the geological history of the materials and the geological environment in which they are now found. Studies to date include the following:
1) The nature and geotechnical influence of mineral boundaries
Little is known about the nature of mineral surfaces, the ways in which they can change with time and the manner in which these changes can affect the properties of rocks and soils. Attention has been paid to the weathering of silicate surfaces (quartz, feldspars, micas, clay minerals and the like) and the role of silica gels on these interfaces. To pursue this studies have been made using the tensile strength of rock to investigate the influence environment has on particle bonding.
Recent PhD theses & Books completed under this theme;
- Kageson-Loe. N.M. 1993 The strain behaviour of Chalk London University
- Park. H-D 1994 Tensile rock strength and related behaviour revealed by Hoop Tests London University
- Passas. N, 1996 Petrophysical; studies of penrith Sandstone pertinent to its behaviour in extension London University
- Al-Derbi, M. S. 1997 Evidence for the constant nature of tensile strength in
Sadus Limestone, Saudi Arabia. London University
- Forero-Duenas, C. A. 1998 Characterisation of a silica gel as a geotechnical cement. London University
- Butenuth. C. 2001 Strength and Weathering of Rock as Boundary layer Problems Imperial College Press 270pp
- Hamm. T. 2002 The response of porous stone to water vapour London University
2) The geotechnical influence of geological history
Much still remains to be known of the ways in which geological history is remembered by soils and rocks, (fissures and joints are well known examples) and thus the data to be collected from site in order to predict the likely response of the ground to this history. Particular attention has been paid to the geological history of Tertiary basins such as the London Basin as it is here that the evidence sought is likely to be most readily revealed.
Current PhD theses under this theme;
- Mannion. W. Stratigraphic studies of relevance to the geotechnics of the London basin (in progress) London University
- Massie (nee Boydell). K. An examination of evidence for a compartmentalized London Basin. (in progress) London University
3) The geological controls on groundwater movement to engineering sites
This is a constant problem that brings many unanswered questions to light. It is not a subject for water supply but for groundwater control and few establishments address this subject from a geological perspective.
Recent PhD theses completed and underway under this theme and Award;
- Boltze. U. 1994 Gas emissions relevant to waste management through water tables in porous media. London University
- Safety in Construction Medal of the Institution of Civil Engineers (with Boltze for work on gas movement through the water table) 1997
- Mohammadi. M,K, 1996 The North Tehran Fault and its contribution to ground water in the Greater Tehran area London University
- Yeo. I-W 1997 Anisotropic hydraulic properties of a rock fracture under normal and shear loading London University
- Zabidi, H,B, The prediction of karst in Kuala Lumper (in progress) London University